Method and apparatus for coating



Feb. 17. 1 925.

L. C. TURNOCK METHOD AND APPARATUS FOR COATING INVENTOR 0. W

Filed Oct. 12,

Patented Feb. 17, 1925.

UNITED STATES LAWRENCE C. TUBNQCN, F EDGEWOOD, PENNSYLVANIA.

METHOD AND APPARATUS FOR COATING.

Application filed October 12, 1923. Serial No. 668,113.

To all whom it may concern:

Be it known that I, LAWRENCE O. TUR- NOCK, a citizen of theUnitedStates, residing at Edgewood, Allegheny County, Pennsylvania,'haveinvented a new and useful Improvement in Methods and Apparatus forCoating, of which the following is a full, clear, and exact description.

. The present invention relates broadly to 1 the coating of objects withmetal, and

more particularly to the coating by electrodeposition of diflerentarticles. The invention is'especially adaptable to the production ofelectrotypes, wherein great accuracy of weight and thickness isdesirable, although the invention is not limited in this respect.

Heretofore in the formation of electrotypes, the thickness of thedeposit has been determined by the sense of-feel with wax cases, and inother cases by a rough approximation based upon time. While some skilledoperators are capable ofjudging the thickness of the deposit by thesense of touch with considerable speed and a fair degree of accuracy,this method, like the other, is largely a matter of approximation only,and can not be applied at all where lead molds are used. By the presentinvention, there is provided a method and apparatus enabling a coatingof the desired thickness to be applied, and then indicating, in somesuitable manner, the attainment of this result. In this way, it ispossible to obtain uniform results in the shortest possible time andwith the likelihood of error reduced to a minimum.

In the accompanying drawings, there is indicated more or lessdiagrammatically, one form of apparatus by means of which my inventionmay .be carried out, it being understoodthat the drawings areillustrative only and do not define the limits of the invention, aschanges may be made therein as desired, without departing from thespirit of my invention or scope of my broader claims.

In the drawings:

Figure l,is a diagrammatic view, partly broken away, illustrating apreferred embodiment of the present invention; and

Figure 2 is a detail View illustratingzone of the switches employed.

In accordance with the present invention,

there may be provided a tank 2, adapted to receive a suitable bath forelectrolytic deposition, as well understood in the art. EX- tendinglengthwise of the tank and supported in any desired cooperative relationthere-- to may be a bus bar 3, adapted to be electrically connected to aseries of anodes A and A, any required number of which may be provided.Cooperating with" the anode A may be a pair of cases C and C, serving ascathodes and adapted to receive the deposit, while cooperating with theanode A is a similar pair of cases C and C The operation of each of theanodes is the same, and the relationship between the anodes and thecathodes is identical. For this reason, it will only be necessary tofully set forth the operation of a single anode and cathode, it beingunderstood that both the anodes and cathodes may be stationary, oreither one or both in motion.

In operation, current flows from a suitable source of electric power tothe bus bar 3, and thence to the anode A. From this anode, there is acurrent flow to the cathode case- C and thence through the connection 4to the wire 5. This wire is operatively connected to one terminal of anampcre-hour or control meter 6, of any standard construction, such, forexample, as the well known Sangamo meter, operating on a time currentflow basis. It is well known that the amount of metal depositedelectrolytically is directly proportional to the current flow, so thatby providing a predetermined current flow for a definite period of time,a deposit of known thickness per unit of surface area can be produced.This makes it unnecessary to keep a separaterecord of the time eachcaseis immersed, or its switch closed, and makes it possible to startdepositing on different cases at different times without keeping anytime record thereof, and insures the simultaneous production of articleshaving either deposits of thesame or different thicknesses, as desired.

The opposite terminal of the meter 6 is electrically connected to thewire 7 leading to the fixed post 8 of a single pole, double throw switch9. This switch is illustrated indetail in -Figure 2. In its -full lineposition, which is the position it normally occupies during theelectrodeposition operation, it in electrical connection with a contact10, while in its upper dotted line position, it is in electricalconnection with a contact 11. In its intermediate dotted line position,the switch is in neutral position, cutting off all current flow.

The switch 9 in Figure 1 being in the full line position of Figure 2,permits the current to flow through the contact 10 to the bus bar 12.From the bus bar 12, the circuit is completed by bus bar 13 to the ter-'minal 11 of a totalizing meter 15. This meter may be ofthe recordingtype, whose function is to add and maintain a permanent record ofoperation of all-the separate control meters 6 on a single board, thusenabling a record to be kept of all metal used. From the meter 15,current flows to contact 16 and bus bar 17 to the bus bar 18, connectedto the opposite side of the source of electric power.

From the foregoing, it will beapparent that with each of the switches inthe position described, current will flow from each of the anodes to therespective cathode cases provided. If for any reason, it is desired todetermine the current flow to any particular cathode, the correspondingswitch will be 'pulled to its upper dotted line position tobring it intoelectrical connection with the contact 11 and permit current to flow tothe bus bar 19. This bus bar is electrically connected to one terminalof an indicating meter 20, the opposite terminal of which is connectedto the bus bar 13. In this manner, the flow of current between any anodeand cathode may be ascertained without interfering with the function ofthe meter 15. If desired, this indicating meter may have a specialscale, in addition to the ampere scale, which will read in thecorresponding weight units. of metal deposited per hour.

In order to indicate the operationof any particular cathode, there maybe provided indicating means of suitable character, showing whether theswitches 9 are closed or open. While this indicating means may be visualor audible, I have indicated lamps for this purpose. With a switchclosed, current will flow from bus bar 3 to wire 21, connected to eachof the white lamps,

1, 1', 1 and .1 by separate lead wires 22,

. and connected to each of the red lamps L, L,

This indicating meter is desirable, as it serves to quickly indicateeither proper or faulty operating conditions. For example, too low a,current flow may indicate improper contact,too low bath potentialor'improper spacing of anode or' cathode. Too

high a current flow, on the other hand, may indicate too high bathpotential, improper anode and cathode spacing, contributing to interiormetal deposits.

The opposite side of each of the red lamps may be connected by a lead 25to a terminal 26 onits cooperating control meter 6. This terminal is inelectrical connection, as indi cated by dotted lines in Figure 1, withthe pointer of the meter. In addition to the regular pointer, there maybe provided an auxiliary indicating hand 27, which can be manually movedto any position, the position selected depending upon the weight ofmetal to be deposited. With this construction, when the pointer reachesa position corresponding to that of the hand H, current will flowthrough such lamp and the pointer to the hand 27 electrically connectedto the terminal 28. Each terminal 28 is, in turn, connected to thecorresponding meter wire 7. Thus, when the pointer of any meter 6reaches a position coinciding with its auX iliaryhand, both the whitelight and the red light for such meter will be lighted.

Preferably, the connections are such that the lighting of any red lightwill indicate I that a deposit of the desired thickness has been made onits corresponding cathode. This is accomplished by calibrating themeters in any suitable manner, as for instance, to correspond to theweight of the metal deposited. As the weightot metal distributed over agiven area controls the thickness, it is possible by initially settingthe auxiliary hand at the desired point to definitely indicate when suchweight and thickness of metal has been deposited. As the movement of thepointer is dependent upon both time and current flow, it will beapparent that when any pointer reaches a position coinciding with thatof its auxiliary hand. the coating on a particular cathode will becompleted. This will be shown not only by the position of such pointer,but by the indicatingmeans L,L',

With the present invention. the meter 15 will show the total metaldeposited over any period of time, While the meter 20 makes it, possibleto quickly show the individual current flow, or corresponding rate ofmetal deposition, to any one cathode. Any desired number of anodes andcathodes may be provided and the same results obtained. It will beobvious that while I have herein referred to cases such as used in theelectrotyping industry. the utility of the invention is not limited inthis respect, but is equally adaptable to controlling metal deposits toindividual articles of any nature, such as now coated by other methods.

Further advantages arise from the provision of means making it possibleto alwa s secure a coating of any desired and pr e and means forindicating the total deposited on all of said cathodes.

termined thickness. This insures uniformity in the deposit on thearticles coated, irrespective of their nature or character.

Still further advantages arise from the provision of indicating meanscalling attention to the completion of the deposit on any cathode.

Still other advantages arise from the provision of means making itpossible to obtain at any instant the current flow or rate of metaldeposition to each individual article to be plated, thereby quicklyindicating proper or improper operating conditions.

I claim:

1. In the method of electroplating, the steps .consisting of submerginga plurality of articles to be coated as cathodes in a bath incooperative relation to a source of coat: ing metal, and separatelyindicating the deposit on each article.

2. In the method of electroplating, the steps consisting of submerging aplurality of articles to be coated as cathodes in a bath in cooperativerelation to a source of coating metal, separately indicating the depositon each article, and indicating the total metal deposited on all of saidarticles.

3. In the method of producing electrotypes, the steps consisting ofsubmerging a plurality of cases as cathodes in a bath in cooperativerelation to at least one anode,

and separately indicating the deposit on each case.

4. In the method of producing electrotypes, the steps consisting ofsubmerging a plurality of cases as'cathodes in a bath in cooperativerelation to at least one anode, separately indicating the deposit oneach case, and indicating the total deposit on all of said cases.

5. In an apparatus for electroplating, a bath having at least one anodetherein, a plurality of articles to be coated arranged as cathodes incooperative relation thereto, and separate indicating means for eachcathode.

6. In an apparatus for electroplating, a bath having at least one anodetherein, a plurality of articles to be coated arranged as cathodes incooperative relation thereto, separate indicating means for eachcathode, metal 7. In a apparatus for electroplating, a bath having atleast one anode therein, a plurality of articles to be coated arrangedas cathodes in cooperative relation thereto,

separate indicating means for each cathode,

and other means for indicating the completion of the coating operation.

8. In an apparatus for electroplating, a bath having at least one anodetherein, a plurality of articles to be coated arranged as cathodes incooperative relation thereto, separate indicating means for eachcathode, and means adapted to be operativel connected at will to any ofsaid catho es for indicating the operation thereof.

9. In an apparatus for electroplating, a bath having at least one anodetherein, a plurality of articles to be coated arranged as cathodes incooperative relation thereto,

and means adapted to be operatively connected at will to any of saidcathodes for indicating the operation thereof.

10. In an apparatus for electroplating, a bath having at least one anodetherein, a plurality of articles to be coated arranged as cathodes incooperative relation thereto, separate indicating means for eachcathode, means for indicating the total metal deposit on all of saidcathodes, and means adapted to be operatively connected at will to anyof said cathodes for indicating the operation thereof.

1 11. In an apparatus for electroplating, a

bath havin at least one anode therein, a plurality 0 articles to becoated arranged as cathodes in. cooperative relation thereto, means forindicating the total metal deposit on all of said cathodes, and meansadapted to be operatively connected at will to any of said cathodes forindicating the operation thereof.

12. In the method of electroplating, the steps consisting of providing aplurality of cathodes in a single bath in cooperative relation to asource of coating metal, and sglparately connecting a meter to eachcatho e.

13. As an article of manufacture, a current flow meter for use inelectroplating, having a dial graduated to indicate the rate at whichthe metal is deposited.

14. The method of electroplating a plurality of articles in a platingbath, which includes dividing the articles among a plurality of cathodesin the same bath and separately measuring the quantity of metaldeposited on each cathode.

In testimony whereof I have hereunto set my hand.

LAWRENCE oTUaNoo

